The present methods, devices, and systems relate generally to the field of image guided surgery, and with the registration of one or more patient images to an object (such as a tool or instrument, and more particularly a surgical tool or instrument) relevant to the procedure. An example of a surgical robot that can be used in a procedure to which the present registration methods, devices, and systems relate is disclosed in U.S. Pat. No. 7,155,316, which is incorporated by reference. Examples of registration techniques, not necessarily associated with surgical robots, are included in U.S. Patent Application Publication No. US 2005/0054910 A1, which is incorporated by reference.